<table border="1" cellspacing="0" cellpadding="8">
    <tr>
        <th>Issue</th>
        <td>
            <a href=https://github.com/llvm/llvm-project/issues/63689>63689</a>
        </td>
    </tr>

    <tr>
        <th>Summary</th>
        <td>
            [PowerPC] Wasn't expecting to be able to lower this! UNREACHABLE executed at /usr/src/contrib/llvm-project/llvm/lib/Target/PowerPC/PPCISelLowering.cpp:11299!
        </td>
    </tr>

    <tr>
      <th>Labels</th>
      <td>
            new issue
      </td>
    </tr>

    <tr>
      <th>Assignees</th>
      <td>
      </td>
    </tr>

    <tr>
      <th>Reporter</th>
      <td>
          pkubaj
      </td>
    </tr>
</table>

<pre>
    FreeBSD 14.0-CURRENT
powerpc, powerpc64, powerpc64le
LLVM 16.0.6

Test case:
```
extern "C" int abs(int);
struct {
  int width;
} __trans_tmp_1, Bayer2RGB_VNG_8u_size = __trans_tmp_1;
struct AutoBuffer {
 AutoBuffer(long);
};
void Bayer2RGB_(int, int, int);
int Bayer2RGB_VNG_8u_code, Bayer2RGB_VNG_8u_bstep, Bayer2RGB_VNG_8u_brows,
 Bayer2RGB_VNG_8u_bcn,
    Bayer2RGB_VNG_8u_N = Bayer2RGB_VNG_8u_size.width, Bayer2RGB_VNG_8u_N3,
 Bayer2RGB_VNG_8u_N7,
    Bayer2RGB_VNG_8u_bufstep = Bayer2RGB_VNG_8u_N7 * Bayer2RGB_VNG_8u_bcn,
    demosaicing_dcn, demosaicing_code;
unsigned short Bayer2RGB_VNG_8u_buf;
void Bayer2RGB_VNG_8u(int srcmat, int dstmat) {
  Bayer2RGB_(srcmat, dstmat, Bayer2RGB_VNG_8u_code);
  int i;
 AutoBuffer(Bayer2RGB_VNG_8u_bufstep * Bayer2RGB_VNG_8u_brows);
  unsigned char *srow;
  for (int dy = 0; dy <= 1; dy++) {
    unsigned short *brow = &Bayer2RGB_VNG_8u_buf;
    for (; i < Bayer2RGB_VNG_8u_N; i++, srow++, brow++)
      brow[Bayer2RGB_VNG_8u_N3] = abs(srow[1] - srow[Bayer2RGB_VNG_8u_bstep]);
  }
}
```

Compile with:
`/usr/bin/c++ -cc1 -triple powerpc-unknown-freebsd14.0 -emit-obj -target-cpu pwr9 -O1  -fcxx-exceptions -fexceptions -vectorize-loops demosaicing-7698e9.cpp`

Output:
```
Wasn't expecting to be able to lower this!
UNREACHABLE executed at /usr/src/contrib/llvm-project/llvm/lib/Target/PowerPC/PPCISelLowering.cpp:11299!
PLEASE submit a bug report to https://bugs.freebsd.org/submit/ and include the crash backtrace, preprocessed source, and associated run script.
Stack dump:
0.      Program arguments: /usr/bin/c++ -cc1 -triple powerpc-unknown-freebsd14.0 -emit-obj -target-cpu pwr9 -O1 -Weverything -fcxx-exceptions -fexceptions -vectorize-loops demosaicing-7698e9.cpp
1. <eof> parser at end of file
2.      Code generation
3.      Running pass 'Function Pass Manager' on module 'demosaicing-7698e9.cpp'.
4. Running pass 'PowerPC DAG->DAG Pattern Instruction Selection' on function '@_Z16Bayer2RGB_VNG_8uii'
#0 0x0000000015acd96c PrintStackTrace /usr/src/contrib/llvm-project/llvm/lib/Support/Unix/Signals.inc:567:13
#1 0x0000000015acb288 RunSignalHandlers /usr/src/contrib/llvm-project/llvm/lib/Support/Signals.cpp:103:5
#2 0x0000000015ace2d0 SignalHandler /usr/src/contrib/llvm-project/llvm/lib/Support/Unix/Signals.inc:0:3
#3 0x000000081810c720 handle_signal /usr/src/lib/libthr/thread/thr_sig.c:303:3
```

It seems to build with main branch, would it be possible to cherry-pick the fix to 16?
</pre>
<img width="1px" height="1px" alt="" src="http://email.email.llvm.org/o/eJzEV0lv47gS_jX0pSBBoizLPvjgJe5pIJMJku4Z4F0MiirZ7MikwKXtzK9_ICVviRO8rfEMw2YtZH31sViUmDFiIxGnJJ-TfDlgzm6VnrYvrmQ_BqWqXqcrjTh_XkI6jJNo8f3p6e7hG0mWJJm1ao-65YQuoB-OhldCg53j_f2fv0M6ipN41Cm6329oLHBmkGS9hoyS_htEPFjUEgilC0IpCGmBlYbQsZCW0AnJ5p2fsdpxC6ToZQiue1HZ7cmHFEtYr61m0qztrl2nHumcvaKmT1_m6z8fvqzHbm3E3wgke-v6JtDMWTV3dY36IuZZSei4UXJziZAUy9P4pxLVReRjOgu4_DtP9am8w8lVhTcTKI3F9rZFq70hdNHDfW_n8mwFeO_wEIi5SVnccX0r7EP2ScyH4vOQpat9PrcDPxRA6L-QSIU7ZZjgQm7WVbBdqQKVR7KdDOehArNV-gbvpas_2sfOo9tNMJrv2HE3oTI2SJPLEr2qgLP_0fcGld2mnyujK3Nxlq9K8GMyb5LWVcfl4icu-JZpP8totb-w18prQ7rVa9iihGTzbrzwYtqJhM7D9yr7i-U7qgmdeQxhHUJHnzLvp_fRfQjhA96oj2A7Rl9AgH-Sygtpcl4WOkM-v1XI-TLA63qQ6fxSr43AfDCrO4_58ppa3w5OfeFW5-t-F2rXigZhL3wju-iRdOWMJnRVCknoind5QMR5CpHVom3w2IQjJ1-k2suo1oilqXwXhwh3wkaq_AGRZXqDNuKtg3avJxD9kQJENT8cIjxwbK1Q0kBUXwo_kVulxd8YNUq15vI0RcVoMsZJzNv2TS5_ONs6-1Gn_4sZSWhhAQ8tcivkBqyCEoGVDfph49MBuxWG0LSb8_3h6W62-G02v78DPCB3FitgvpJ6dozmnh0lrRYloaum-bmLWq1-ILe96P-C7VvggdDVow_0uPCjx8XXZ2zuvULITcgpm6UpnUxOGB7v72bPd2BcuRMWGJRuAxpbX9BWwdba1viU6cpvltuYuN-GWOmNRxjmEboCJisQkjeuQrBbBK6Z2ULJ-IvVjIde32psteJojD80yulO7WcyYxQXzBOgnQTDtWht3EF8toy_QOV27Yn8JO5K_VGrjWY7YHrjdiitxwq_uLiiv_An6le79Xv8vym0kFMa-y6AqibZHbRMG9S-GFBWoGqoxfFZhPa5L1SFsEGJmvlonTHrjU9OSo-vZcYAocXKSe694NErfmeSbXyPLUBJ2KnKNei9PoBHi34nhvG7hftqg-XsS0Syu-XsCzwyG556vsruacOHfcYGw6iPWR_xEFqQYbL-R_quYQrhbd1Zo1kCySHpP2nOeDUZcXjUQtpQHt98jf1nB-fZtb7cCV19l-LgFWIjWWNiITnJZvmo8IcmOyFJ3yAp6Xjsaemm_cZk1aA2_y2WI4j-zCaZh3LCQN9gQFolcAXgl3CRkGx2JiI7gxin4zThBU1gG8KvTZj3FkQXpBGl3Xql3WpkVTfwM2IfIwupZp9cKl8tGMSdCQ3WiaYK1wvsmJBQaiZ5eI7bK9dUIKzvwa0yRvR9mG9R69eoFfwl9KlaHLw6HZFsNaimWTXJJmyA03Q0HudFkhejwXY6zBjmE2RJNS6HOdZlOayxLiZJWWbVkNGBmNKEZkmR5GlOaT6KWY75aJgPi7zOi2yck2GCOyaa2PPtm-dAGONwOspG48mgYSU2JrzDUCpxD8FIKPWvNHoatsx3XzJMGmGsOa9ihW3Cy8-x7edL-PfuIvj_XkMDp5vp9T2zEXbrypir3cXq1zEDP4bQVeDvnwEAAP__1qpSIQ">